# dict = {1: "one", 2: "two", 3: "three"}
# print(dict["one"])
# dict1 = {1: "one", 2: "two"}
# print(dict1.pop(1))
# # print(dict1.popitem())
# print(dict1)
# num1 = {1, 2, 3, 4, 5, 6}
# num1.add(7)
# print(num1)
# num1.remove(2)
# print(num1)
# str1 = "abcd"
# str2 = list(reversed(str1))
# print("".join(str2))
#斐波那契数列
# def Fibonacci(n):
#     # write code here
#     if n == 1 or n == 2:
#         return 1
#     f1 = 1
#     f2 = 1
#     for i in range(3,n+1):
#         f3 = f1 + f2
#         f1 = f2
#         f2 = f3
#     return f3
# n = int(input("请输入一个整数："))
# m = Fibonacci(n)
# print(m)
#反转字符串
#发现列表不能强转字符串，字符串不能强转列表
def solve(str):
    str = str[::-1]
    return str
str = input("请输入一个字符串：")
str1 = solve(str)
print(str1)
